\begin{tikzpicture}
    \pgfmathsetmacro{\factor}{0.1}
    \pgfmathsetmacro{\R}{30*\factor}
    \pgfmathsetmacro{\r}{18*\factor}

    \tkzDefPoint(0,0){O}
    \tkzDefPoint(60:\r){A}
    \tkzDefPoint(0:\r){B}
    \tkzDefPoint(60:\R){C}
    \tkzDefPoint(0:\R){D}

    \tkzFillSector[pattern={mylines[angle=45, distance={3pt}]}](O,D)(C)
    \tkzFillSector[white](O,B)(A)

    \tkzDrawArc[thick](O,B)(A)
    \tkzDrawSector[thick](O,D)(C)
    \tkzLabelPoints[left](O,A,C)
    \tkzLabelPoints[below](B,D)
\end{tikzpicture}

